Stacking device for coil springs

ABSTRACT

A stacking device for helical coil springs which have a final coil at each end that terminates in a knot. The stacking devices is of the type having a frame with side walls and a floor defining a guide channel to which the coil springs are supplied by a transfer arm and within which the coil springs are advanced forwardly for stacking. The coil spring is received by rigid converging guide flaps which slightly compress the coil spring. Slide bars are provided which are reciprocally movable on the frame longitudinally of the guide channel. A pair of advancing plates are carried on the slide bars and are spaced inwardly of the guide channel side walls for receiving the coil spring in slightly compressed condition from the guide flaps. The slide bars are operative following reception of the coil spring by the advancing plates to move the advancing plates rearwardly causing the coil spring to slide off the advancing plates and expand axially for engagement with the guide channel side walls whereupon the slide bars are operative to move the advancing plates forwardly so that each of said advancing plates engages the knot in the final coil at the associated end of the coil spring to simultaneously partially rotate and advance the coil spring into stacking relationship with the preceding coil spring. Alignment means are provided including a normally raised striking element operative when the coil spring has been advanced into stacking relationship with the preceding coil spring to move downwardly against the coil spring urging the coil spring into contact with the floor of the guide channel.

. United States Patent 1151' 3,688,918 Sept-5, 1972 Spiihl [72]Inventor: Walter O. Spiihl, St. Gallen, Switzerland v [73] Assignee:Spuhl AG, St. Gallen, Switzerland [22] Filed: July 1, 1970 [21] App].No.: 51,455

[30] Foreign Application Priority Data Primary Examiner-Robert J. SparAttorney-Wm. Marshall Lee and James B. Blanchard [57] ABSTRACT Astacking device for helical coil springs which have a final coil at eachend that terminates in a knot. The

, stacking devices is of the type having a frame with side walls and afloor defining a guide channel to which the which the coil springs areadvanced forwardly for stacking. The coil spring is received by rigidconverging guide flaps which slightly compress the coil spring. Slidebars are provided which are reciprocally movable on the framelongitudinally of .the guide channel. A pair of advancing plates arecarried on the slide bars and are spaced inwardly of the guide channelside walls for receiving the coil spring in slightly-compressedcondition from the guide flaps. The slide bars are operativefollowingreception of the coil spring by the advancing plates to movethe. advancing plates rearwardly causing the coil spring to slide offthe advancing plates and expand axially for engagement with the guidechannel side walls whereupon the slide bars are operative to move theadvancing plates forwardly so that each'of said advancing platesengagesthe knot in the final coil at the associated end of the coil spring tosimultaneously partially rotate and advance the coil spring intostacking relationship with the preceding coil spring. Alignment meansare provided including a normally raised striking element operative whenthe coil spring has been advanced into stacking relationship with thepreceding coil spring to move downwardly against the coil spring urgingthe coil spring into contact with the floor of the guide channel.

7CIaims,9DrawingFigures' Patented Sept. 5, 1972 4 Sheets-Sheet 1Patented Sept. 5, 1972 4 Sha na-Sheet 2 Patented Sept. 5, 1972 Q 4Sheets-Shoat 3 Patented Sept. 5,1912 3,688,918

4 Sheets-Sheet 4 I I STACKING DEVICE FOR COIL SPRINGS The inventionconcerns a stacking device for coil springs which have final coils thatend in knots, the machine having a guide channel for the coilspringswhich are automatically supplied with the knot lying on top, a slide barwhich can be moved backwards and forwards in the guide channel and whichis provided with advancing plates on both sides, an element which can bemoved up and down in time with the slide bar movement approximatelyperpendicular to the plane in which the springs advance and which actsupon at least one of these, and also means in addition in order to obtain a rotation of the knots by about 90 while making use of a coilguide caused by the springs which have already been stacked. Such adevice has been shown in the German Pat. No. 1,241,403 by the sameapplicant. In the case of the well known device, the element which canbe moved up and down has an oblique edge at the bottom which comes intocontact with the knot of the one final coil of the spring which issupplied in the course of the downward motion of the element and therebycauses the rotation which screws in the spring into the springs whichhave already been stacked. The present invention has the object ofimproving and simplifying this device which was already very progressivecompared to the earlier state of the art, namely with respect to an eventighter stacking and an even more reliable method of operation,particularly for the case that the springs are not sufficiently-free ofdefects. This is accomplished according to the invention by means of thefact that the final coils of the springs which at that moment are beingsupplied to an operating cycle are supported in the guide position onthe advancing plates from which they slide off in the course of abackward movement of the slide bar whereupon they come to rest partiallyupon parts of the rigid frame and partially overlapping onto the finalcoils of the immediately preceding springs, while the body of the springwhich is being supplied is still held in the supply position and that inthe course of the forward movement of the slide bar which then follows,the front edges of the two advancing plates carry along the knots of thetwo final coils of the supplied springs which project toward the insideand thereby effect both the complete advance of the supplied springs inthe guide channel as well as the rotation of the knots and that inaddition, the element which can be moved up and down has a pressure footin order to press down the immediately preceding spring onto the floorof the guide channel by means of striking upon at least one of its finalcoils during the operating cycle which is being considered. Therefore,the rotation is caused simultaneously on the knots of both final coilsof the springs which are supplied and without any increased effort.

On the contrary, the advancing plates can now consist simply of a sheetof constant thickness and not, as previously, be made of relativelythick plates which are worked into a wedge shape.

Additional characteristics and advantages of the invention will be seenfrom the following description as well.

An exemplified embodiment of the object of the invention is shownschematically in the drawings. The drawings show the following:

FIG. 1, a longitudinal cross section through the stacking device in thevertical midplane of the guide channel in a first phase of its operatingcycle,

FIG. 2, a portion of the device in a top view corresponding to FIG. 1,

FIG. 3, a portion of the device in a side view corresponding to FIG. 1,

FIG. 4, the same longitudinal section as in FIG. 1, but in a secondoperating phase,

FIG. 5, a portion of the device in a top view corresponding to FIG. 4,

FIG. 6, the same longitudinal cross section as in FIG. 1, but in a thirdoperating phase,

FIG. 7, a portion of the device in a side view corresponding to FIG. 6,

FIG. 8, the same longitudinal cross section as in FIG. 1, but in afourth operating phase, and

FIG. 9, a cross section according to line IXIX in FIG. 8.

In order to simplify the comparison, the same reference signs are usedin the drawings for the corresponding parts as in the patent which wasmentioned at the beginning.

The stacking device has a guide channel 1, the floor of which is formedby a base plate 2 which is attached rigidly to the frame, while its sidewalls, of which only one is shown in FIGS. 3 and 7, each have twohorizontal rods 3 and 4 which are parallel to each other. The rods ofeach side wall which are attached rigidly to the frame are connectedwith the base plate 2 and with each other at their right ends on theoutlet side in FIG. 1 by one vertical post 5 each which is mountedexternally on these rods and which has been omitted in FIGS. 3 and 7. Atthe left end of each pair of rods 3 and 4, on the inlet side, avertical, rectangular metal plate 7 is attached on the inside of thepair of rods over two vertical metal strips 41. An edge 42 on the rightside (see FIG. 2) of plate 7 is bent slightly toward the rods 3 and 4corresponding to the thickness of the strips 41. However, plate 7 canalso be fastened directly to rods 3 and 4, in which case the inclinededge 42 is unnecessary. Two guide flaps 9 which diverge downward areprovided below plates 7 and are fastened to rods 3 by means of flanges43. which are bent around horizontally so that the upper edge 44 of theguide surface of flap 9 projects toward the inside somewhat beyond plate7.

The guide flaps 9 serve to guide the two final coils 10 of a double-conecoil spring 11 which is held at its midpoint by the free end of an arm12 of the transport device, for example, by means of a hook which hasnot been shown. The arm supporting the spring 11 rotates in acounterclockwise direction to FIG. 1 and thereby brings the spring inbetween the two guide flaps 9 by means of which the spring is lightlypressed together. In the course of further rotation of the arm, thefinal coils 10 of the spring 1 1 glide over the edges 44 onto twoadvancing plates 21 which belong to a slide bar 14.

means of a vertical strip 45 and at their ends on the right side bymeans of a vertical strip 46. A small block 20 is fastened above rod 15on strip 45 and supports the plate 21 which has already been mentioned.Strips 45 and 46 are located on the outside of the rods 15 and 16 and,in contrast to a connection strip previously attached to their insides,do not participate in the progression of the springs 11 in the guidechannel. On each side of the slide bar 14, two guides 23 shown only inFIGS. 4 and are shown between which there is a roller 24 which ismounted on the end of a lever 25 belonging to the transport device, thelever being moved periodically back and forth in the sense of the doublearrow 26, whereby the slide bars 14 are shifted back and forth in thesense of the double arrow 27 along rods 3 and 4.

In order to press down the springs 11 which are advanced forward in theguide channel by the slide bar 14 in a way which will be explained inmore detail below and stacked in each other, a rocker arm 29 is providedwhich is provided at one end with a bearing eye 30 which is supported sothat it can be moved on an offset peg 31 which is located at the upperend of the post 5 which is shown. A feeler roller 32 is attached to therocker arm 29 by means of a screw 33, the bolt of which is cut 011'smoothly and upon which roller 32 can rotate. A pin 34 is screwed tightto the rocker arm 29, and the upper end of a tension spring 35 isfastened to the free end of the pin 34; the lower end of the tensionspring, which is not shown, is fastened to the frame. The tension spring35 holds the feeler roller 32 in contact with a profile cam 36 which isfastened to the upper rod which is visible in the figures and which hastwo horizontal cam surfaces 36a and 36b which are present through a camsurface 360 falling in the advance direction of the springs l 1. It canbe seen that the rocker arm 29 is movedup and down in the sense of thedouble arrow 37 by means of the movement of the slide bar 14 back andforth.

A plate 38 is fastened to the free end of rocker arm 29 and, by means ofscrews 47 which go through the adjustment slot 48 provided in plate 38,are fastened to the adjustment slot. In contrast to the previous case,plate 38 does not have any edge on its lower side which can grasp a knot28 present in a final coil 10 of the spring 11 in question in order torotate the knot into a position which is suitable for tight stacking ofsprings 11 and thereby screw in" this spring into the springs which havealready been stacked. Instead of this, a bottom edge strip 49 has beenbent out of the plane of plate 38 so that it forms a-pressure footwhich, in the course of the downward movement of rocker arm 29, strikesupon the final coil 10 of the spring 11 which is in question and hasalready been moved forward and screwed into the preceding spring andpresses the spring in question down to the floor 2 of the guide channel1.

In the following section, the manner of operation of the device which isdescribed will be explained in even greater detail.

As already mentioned above, the final coils 10 of the spring 11 which isheld by the transport arm 12 and slightly compressed by the guide flaps9 in the supply position according to FIGS. 1-3 first reach the slideplate 21 and not, as previously, the plates 7 which are fastened rigidlyto the frame. The slide bar 14 which is operated by levers 25 throughthe rollers 24 and the guides 23 now moves from its initial position,not forward as previously, but backwards, that is, according to arrow 50in FIG. 1 opposite to the direction of advance in the guide channel 1.In the course of this, spring 1 1 is still held tightly by arm 12 whichremains in its position so that the final coils 10 finally slide off theslide plates 21 onto the plates 7 which are attached rigidly to theframe and thereby each come to lie overlapping on their right side onthe left side of the corresponding final coil 10 of the preceding springas is shown in FIGS. 4 and 5.

Of the springs 11 already located in the guide channel 1, only the finalcoils 10 with the accompanying knots 28 are represented in the drawingsfor the sake of clarity.

If the slide bar 14 now moves toward the front according to arrows 51 inFIGS. Sand 6 starting from its final position at the left, then itsfront edge 52 strikes upon the final coil 10 on the knot 28 ofspring 11which projects inward from the final coil 10, the body of which is stilllocated in the supply position, and thereby moves this forward in theguide channel or into the stacked springs which are already in thesupply channel. By means of guiding the springs which are alreadystacked, the new spring will be screwed into these in the course ofthis, whereby knot'28 which is lying toward the top in the initialposition is rotated by almost into the position of the knot designatedwith 28, in FIG. 1. It can therefore be seen that the edge 52 of theslide plate 21 surprisingly not only causes the advance of spring 11 butalso the rotation of the knots which is required for tight stacking. Forthese functions, according to the patent which was mentioned at thebeginning and which already provided great simplification compared toearlier technology, it was still necessary to have a slide bar 14 thatacted upon the springs with two stages 7, 19 in two successive operatingcycles and an oblique edge 38a of a plate-shaped element 38 which couldbe moved perpendicularly to the plane in which the springs wereadvanced, whereby the reference numbers given in parentheses refer tothe drawings in the above mentioned patent. To be sure,

the present stacking device also has the plate 38 which can be moved upand down and which has a movement mechanism that is very similar to thatof the previous plate-shaped element 380. However, plate 38 is notprovided with an edge which is suitable for rotating the knots, butrather with a pressure foot 49 which, for example, could also beattached to the lower end of a vertically positioned rod. During theoperating cycle under consideration, pressure foot 49 presses upon thefinal 'coil 10 of the spring which has advanced last and possibly alsoupon the final coil of the additional previously advanced spring on thefloor of the channel as is shown in FIG. 4. This guarantees a verycompact stacking of the springs which is corrected perfectly even in thevertical direction and even in the case of springs which have a diameterof the final coil that varies within a relatively large range.

The new stacking device stacks more compactly and, above all, morereliably than the previous stacking device, whereby the circumstancethat the knots on both final coils of the springs are rotated and notonly one of them is rotated has a favorable effect. In addition, thestacking is also perfect when the springs have defects, for example, asa result of deficient quality in the wire which was used or they havefinal coils which do not lie in planes exactly perpendicular to the axisof the spring because of incorrect adjustment of the springmanufacturing apparatus.

Finally, the construction of the slide bar is also more simple becausethe slide plates are simply punched sheet metal plates while relativelyheavy tapered plates were provided previously which had to be processedon one side and were therefore considerably more expensive to acquire.This tapering which was necessary in order not to hinder the supply ofsprings received by the transport arm before the slide bar had reachedits final position at the inlet side is naturally superfluous in thecase of the device which is described.

What is claimed is:

1. In a stacking device for helical coil springs which have a final coilat each end that terminates in a knot, the stacking device being of thetype having a frame with side walls and a floor defining a guide channelto which the coil springs are supplied by a transfer arm in anorientation with the knots on top and within which guide channel thecoil springs are advanced forwardly for stacking, the combination withsaid frame comprismg:

entrance means affixed to said frame for receiving and slightlycompressing a given coil spring being supplied to said guide channel onsaid transfer arm;

slide means reciprocally slidable on said frame longitudinally of saidguide channel; and

a pair of advancing plates carried by said slide means and spacedinwardly of said guide channel side walls to receive said given coilspring on said transfer arm from said entrance means, said slide meansbeing operative following reception of said given coil spring on saidtransfer arm by said pair of advancing plates to move said advancingplates rearwardly causing said given coil spring to slide off saidadvancing plates and expand for engagement with said guide channel sidewalls to permit release of said given coil spring by said transfer armwhereupon said slide means is operative to move said advancing platesforwardly so that each of said advancing plates engages the knotoriented at the top of the final coil of said given coil spring at theassociated end of said given coil spring to simultaneously partiallyrotate and advance said given coil spring into stacking relationshipwith the preceding coil spring.

2. The combination defined in claim 1 further comprising alignment meansincluding a normally raised striking element movable in a verticalplane, said alignment means being operable when said given coil springhas been advanced into stacking relationship with the preceding coilspring to cause said striking element to move downwardly against saidgiven coil spring urging said given coil spring downwardly into contactwith the floor of said guide channel.

3. The combination defined in claim 2 wherein said striking elementincludes a pressure foot for pressing against at least one of the finalend coils of said given coil spring when said striking element movesdownwardl a ains said ven coils 'n 4. The c m ination d ined in cl iinwherein said entrance means comprises a pair of rigid guide flapsaffixed to said frame and converging toward said guide channel toslightly compress said given coil spring.

5. The combination defined in claim 4 wherein said guide flaps haveupper edges which project inside the side walls of said guide channel sothat the final end coils of said given coil spring slide from said guideflaps onto said advancing plates when said advancing plates receive saidgiven coil spring from said entrance means.

6. The combination defined in claim 1 wherein said advancing plates havethe same thickness everywhere.

7. In a stacking device for helical coil springs which have a final coilat each end that terminates in a knot, the stacking device being of thetype having a frame with side walls and a floor defining a guide channelto which the coil springs are supplied by a transfer arm in anorientation with the knots on top and within which guide channel thecoil springs are advanced forwardly for stacking, the combination withsaid frame comprismg:

a pair of rigid guide flaps affixed to said frame and converging towardthe guide channel for receiving and slightly compressing a given coilspring being supplied to said guide channel on said transfer slide meansreciprocally slidable on said frame longitudinally of said guidechannel;

a pair of advancing plates carried by said slide means and spacedinwardly of said guide channel side walls .to receive said given coilspring on said transfer arm from said pair of rigid guide flaps, saidslide means being operative following reception of said given coilspring on said transfer arm by said pair of advancing plates to movesaid advancing plates rearwardly causing said given coil spring to slideoff said advancing plates and expand for engagement with said guidechannel side walls to permit release of said given coil spring by saidtransfer arm whereupon said slide means is operative to move saidadvancing plates forwardly so that each of said advancing plates engagesthe knot oriented at the top of the final coil of said given coil springat the associated end of said given coil spring to simultaneouslypartially rotate and advance said given coil spring into stackingrelationship with the preceding coil spring; and

alignment means including a normally raised striking element movable ina vertical plane, said alignment means being operable when said givencoil spring has been advanced into stacking relationship with thepreceding coil spring to cause said striking element to move downwardlyagainst said given coil spring urging said given coil spring downwardlyinto contact with the floor of said guide channel.

1. In a stacking device for helical coil springs which have a final coilat each end that terminates in a knot, the stacking device being of thetype having a frame with side walls and a floor defining a guide channelto which the coil springs are supplied by a transfer arm in anorientation with the knots on top and within which guide channel thecoil springs are advanced forwardly for stacking, the combination withsaid frame comprising: entrance means affixed to said frame forreceiving and slightly compressing a given coil spring being supplied tosaid guide channel on said transfer arm; slide means reciprocallyslidable on said frame longitudinally of said guide channel; and a pairof advancing plates carried by said slide means and spaced inwardly ofsaid guide channel side walls to receive said given coil spring on saidtransfer arm from said entrance means, said slide means being operativefollowing reception of said given coil spring on said transfer arm bysaid pair of advancing plates to move said advancing plates rearwardlycausing said given coil spring to slide off said advancing plates andexpand for engagement with said guide channel side walls to permitrelease of said given coil spring by said transfer arm whereupon saidslide means is operative to move said advancing plates forwardly so thateach of said advancing plates engages the knot oriented at the top ofthe final coil of said given coil spring at the associated end of saidgiven coil spring to simultaneously partially rotate and advance saidgiven coil spring into stacking relationship with the preceding coilspring.
 2. The combination defined in claim 1 further comprisingalignment means including a normally raised striking element movable ina vertical plane, said alignment means being operable when said givencoil spring has been advanced into stacking relationship with thepreceding coil spring to cause said striking element to move downwardlyagainst said given coil spring urging said given coil spring downwardlyinto contact with the floor of said guide channel.
 3. The combinationdefined in claim 2 wherein said striking element includes a pressurefoot for pressing against at least one of the final end coils of saidgiven coil spring when said striking element moves downwardly againstsaid given coil spring.
 4. The combination defined in claim 1 whereinsaid entrance means comprises a pair of rigid guide flaps affixed tosaid frame and converging toward said guide channel to slightly compresssaid given coil spring.
 5. The combination defined in claim 4 whereinsaid guide flaps have upper edges which project inside the side walls ofsaid guide channel so that the final end coils of said given coil springslide from said guide flaps onto said advancing plates when saidadvancing plates receive said given coil spring from said entrancemeans.
 6. The combination defined in claim 1 wherein said advancingplates have the same thickness everywhere.
 7. In a stacking device forhelical coil springs which have a final coil at each end that terminatesin a knot, the stacking device being of the type having a frame withside walls and a floor defining a guide channel to which the coilsprings are supplied by a transfer arm in an orientation with the knotson top and within which guide channel the coil springs are advancedforwardly for stacking, the combination with Said frame comprising: apair of rigid guide flaps affixed to said frame and converging towardthe guide channel for receiving and slightly compressing a given coilspring being supplied to said guide channel on said transfer arm; slidemeans reciprocally slidable on said frame longitudinally of said guidechannel; a pair of advancing plates carried by said slide means andspaced inwardly of said guide channel side walls to receive said givencoil spring on said transfer arm from said pair of rigid guide flaps,said slide means being operative following reception of said given coilspring on said transfer arm by said pair of advancing plates to movesaid advancing plates rearwardly causing said given coil spring to slideoff said advancing plates and expand for engagement with said guidechannel side walls to permit release of said given coil spring by saidtransfer arm whereupon said slide means is operative to move saidadvancing plates forwardly so that each of said advancing plates engagesthe knot oriented at the top of the final coil of said given coil springat the associated end of said given coil spring to simultaneouslypartially rotate and advance said given coil spring into stackingrelationship with the preceding coil spring; and alignment meansincluding a normally raised striking element movable in a verticalplane, said alignment means being operable when said given coil springhas been advanced into stacking relationship with the preceding coilspring to cause said striking element to move downwardly against saidgiven coil spring urging said given coil spring downwardly into contactwith the floor of said guide channel.